A Contract Between Reapers
by ChaoticAscension
Summary: Hei was sent to investigate the possibility of a new type of Contractor within the bounds of Karakura Town - something causing strange accidents without setting off any stars assigned to Contractors. Nothing is ever simple when it involves the Black Reaper.
1. Chapter 1

**A/N: For reasons I hadn't updated in a while, check my profile page. Story-wise: I am amazed at the fact that before this there WERE no Darker than Black/Bleach crossovers – several things seem to be fairly obvious connections between the two, such as Hei's mask and a Hollow/Vizard mask, as well as Hei being referred to as The Black Reaper. For those who haven't heard of Darker than Black before, I recommend you check it out – a very good (although relatively short) sort of dark, fairly realistic and scientific anime. Unlike most others, the abilities within it follow the laws of physics if you truly take a look at what the ability is. Superspeed becomes deadly in bad weather, gravity manipulation affects whether or not one can still stand instead of just having something fall on them, things like that. My hope is to inspire more Darker than Black/Bleach crossovers with this story.**

…...

Fifteen years. It has been fifteen years since the anomalies known as Gates appeared, and replaced the true stars with false ones. One Gate, known as Heaven's Gate, disappeared ten years ago. Although, "disappeared" is not technically the correct term – instead it had formed an impenetrable barrier of some sort around itself and a very large portion of Brazil, where it was located. The other Gate, Hell's Gate, lies in Tokyo, and has not yet done anything of the sort. These Gates are considered by some to be either a punishment or reward by a god – while others consider them to **be** a form of god or divine being in itself. This is due to the curious events that occur within them, where some have reported seeing the true stars again, some have witnessed dead family and friends, and some would simply die. For the safety of the public, Hell's Gate has had a wall built around it to prevent any unauthorized access.

The false stars, it had soon been realized by the governments, represented the lives of people known as Contractors. Contractors appeared to feel and experience no emotion, and instead think and act entirely rationally, with their primary purpose being self-preservation. They also have certain abilities to do what ordinary people cannot, although they have to pay a 'price' afterwards – an obsessive compulsive need to perform one of many various acts – some prices involve self-harm, some involve eating or consuming odd things such as plants, some involve entirely pointless actions such as arranging rocks in a square, or turning down the corner of each page in a book.

There is one Contractor who is infamous among governments and Contractors alike, an anomalous Contractor who does not appear to have a price, and is capable of emotional thought and actions even when they are not, rationally speaking, the best course of action: Messier code BK-201, the Black Reaper. Contractors fear him because to date, he has killed more Contractors than any other single person alive; governments are wary of him because he is not affiliated with any known organization and seems to be unpredictable due to his ability to feel and act on feelings rather than strictly logic. His codename is Hei, although none seem certain whether or not this is his true name. He is a skilled fighter and assassin with the ability of quantum particle manipulation, normally taking the form of electricity, and dislikes other Contractors due to their tendency to sell out anybody in order to preserve their own life.

…...

Hei was startled out of his reverie by the nearby phone ringing. _Finally, another job._ When he answered it, he was shocked by the familiar voice on the phone.

"Is this BK201, codename Hei?"

"Yes. Why are you of all people calling me, Misaki Kirihara?"

"...Well to put it simply, I – and the group I work with – have a job for you."

"And I'm to expect this isn't some sort of trap designed to capture me?"

At this, Kirihara sounded somewhat embarassed. "Actually, it's not, strictly speaking, a job from Section 3... It's more of a job I had for you, as you are the most capable person I could think of for a job like this."

Hei thought about it for a little while. _At least I might as well hear out what she had in mind – if I don't like the way it sounds I can always refuse the job._ "I'm not promising to take on the job yet, but I'm willing to listen and decide if I like it or not. And if the pay is good enough."

"Great. I'll just get to the point then: lately, there have been several strange incidents in a relatively small town in Japan. These incidents involve walls randomly caving in despite being structurally sound and new enough that it shouldn't happen, people getting injured as if attacked by something in broad daylight with no apparent agressor... It sounds like there's a Contractor, or possibly a group of them, who attack random targets and are never seen. The strange part is this has happened during times when not a single star was vibrating, implying it's either a different type of Contractor or something else that isn't represented or trackable. Even the Dolls used by the police can't seem to find anything."

"That's... strange; which town would this be in?"

"It's a place called Karakura."

"And my job is to... what? Find and eliminate whatever threat is there?"

"Not exactly. Your job is to find out what the threat is – if they are Contractors, do with them as you please; if it is something else, I want you to report back with as much information as possible."

"What exactly is the pay, if I do this; and you _do_ realize if they ARE Contractors, I am far more likely to simply kill them instead of trying to find their motives, right?"

"The pay is one million yen upon completion, with one hundred thousand up front. Yes I do realize that... however as I said the decision as to their fates is left to you."

"Very well. I will accept the job for now; after all it is outside of the jurisdiction of any officers you might know well enough to entrust trapping the 'infamous Black Reaper'. I expect you to leave the first payment at the location we were in on the night of the rumor that the stars would return by 8 PM tomorrow. I will not be there myself until an indeterminate amount of time afterwards to reduce the chances of a working trap or ambush."

"That's... fine then. Goodbye, Li."

The call was disconnected. Hei was not certain yet that this was not a trick of some sort – however she _had_ allowed him to name the time and place for her to leave the first payment, and it didn't seem as if she intended to capture him. If it was a trap, why would one of the few people he would know be the one chosen to call him instead of how the last trap went – somebody he didn't recognize offered him an assassination job, he took it and arrived at the set location – only to realize it was a group of Contractors who wanted to take him out before somebody hired him to go after them. Idiots obviously underestimated his skills, considering they thought tying him up instead of killing him was a better idea when he appeared to be unconscious.

…...

A week after picking up his payment, Hei finally arrived in Karakura. Due to this town's only active police force being relatively small and not in contact with the Tokyo police, he had decided to use his old, already-established alias of Li Shengshun, a 24-year old recently out of schooling who wished to travel for a while before settling down with a particular career. So far he had not seen any evidence of these strange occurences, and so he was currently visiting a restaurant. _Sure are some strange people here though – I've seen a teenager with orange hair and a very short temper who appears to be well known enough that most gangs or delinquents either have a problem with him or are terrified of him._ As he sat down to eat, he watched in amusement as the teen he had just thought about walked in with a few others – a dark haired man with glasses and all-white clothing, a man who appeared to be of latin origins and was large enough that he had to duck to walk through the doors, a young woman with orange hair – _perhaps they were family?_ - and a _very_ short woman with black hair whose temper appeared to match that of the orange-haired teen. _Like I said_, he thought, _strange people._

About half an hour later, when Hei had nearly finished his food – with the entire restaurant staring at how much he had ordered – he noticed the group of teenagers gasp in shock just before the wall imploded. _What the-_- he watched as the first teen pressed something to his chest before collapsing, and the short woman swallowed something. The rest of the group appeared to be preparing for a fight of some kind, apparently familiar with such a situation. Hei felt something he couldn't see grab him, and promptly electrocuted it with a bit more than enough to kill your average human. He fell to the floor as whatever it was released him, but he couldn't see anything and it didn't appear to have killed it. _What the hell is this thing?_ The next thing he knew he had gotten hit – hard – across the head, and was staring at – himself?

Taking a quick look at the situation, he seemed to suddenly have a chain stuck to his chest, and could see a pool of blood forming under the other him. Hearing a voice, he looked over and-

He could finally see the thing that had attacked. It was large, bone-white, wearing a mask not too dissimilar from his own except for the design, and had a large black hole in its chest. One of its hands appeared to be smoking slightly. _Must have been the one that grabbed me..._ He could also see a grim look in the eyes of the teenagers nearby. The one with glasses had some sort of bow in his hand, the large man's arm was a strange coloring of black and a reddish-purple, the young woman was looking at him with tears in her eyes, and the orange-haired teen and short woman from earlier also appeared to have doubles – they were both wearing black robes and sandals, while wielding swords – more of a cleaver in the teen's hands, really – and all seemed to be fighting against the creature without doing a lot of damage. Curiously, everybody seemed to be aiming directly for its head or mask, and any blows elsewhere didn't quite seem to stick or do much to it.

Thinking quickly, he grabbed the end of the chain stuck to his chest and threw it, one end wrapping around the creature's neck, before sending as much electricity as he could into the chain and thus the creature. He saw the teens stop what they were doing out of sheer surprise while the creature went into spasms and, incapable of dealing with the amount of electricity he was pumping into it, began to disintegrate once the chain and electricity blew apart its mask.

The teens were staring slack-jawed at him. Eventually they seemed to get over the shock enough to speak, and one of them voiced what was on his mind - "Did that plus just- WHAT THE HELL?!"

"Excuse me, but what's a 'plus'?"

…...**_Back in Tokyo_**

The Tokyo police force stared in shock as they watched BK201's star vibrate, then fall from the sky.


	2. Prelude part 2

**A/N: Entirely optional piece, more of an addition to the first chapter than anything. I will be uploading on a weekly basis and will attempt to warn you if I have reason to believe the next week will either contain more than one chapter or for some reason will not have one. As this is an optional piece and not a chapter in itself, this does not count as this week's chapter. On a side note, I am finally back from my work-related trip that I went on immediately after posting the first chapter, and I am somewhat disappointed by the fact that nobody else has yet released a crossover of Bleach or DTB.**

Disclaimer: Neither Bleach nor Darker than Black belong to me; this story does not produce any form of money or profit for me.

_**PRELUDE PART 2 – Ichigo's Point-of-view, Timeline: First Meeting**_

...

"Geez, that hollow last night was a pain in the ass. Bladed fingers, envenomed prehensile spines, and a larger than average reiatsu makes for a long fight."

"Shut up, Kurosaki. You didn't even show up until I had already been fighting it for twenty minutes; the only reason you were able to finish it off was because I already wore it down."

"Well you didn't do a good job of it, considering we kept fighting for another half hour Ishida!"

At this point, Orihime Inoue attempted to step in and calm the two down; "There's no reason to fight each other over this, we still defeated it in the end and nobody got hurt too badly, right?" Needless to say, she was not very successful – not for lack of trying, but because they immediately started blaming each other for the few injuries they had gotten (despite the fact that Orihime had healed each of them while the other distracted the hollow).

Chad, whose actual name was Sado, suggested they continue the argument another time. "We should not be talking about these kinds of affairs in public; people might start to wonder what's going on."

"...I suppose he has a point, Kurosaki. Let's just find a place to sit and order our food. That is, as soon as Kuchiki gets back from wherever she went."

"She said she needed to use the restroom." Ichigo was amazed at how easily the Quincy, Uryu Ishida, could forget something he heard a few minutes earlier considering he was widely considered the most intelligent person in their school.

Approximately fifteen minutes after they received their meals, Orihime pointed out a black-haired young man at another table who seemed to have ordered Chad's weight in food – and didn't seem to be slowing down or believe he would not be able to finish it.

"Hey Rukia, do you think if you ate that much you would finally be able to grow taller?" (This statement resulted in Ichigo getting smacked in the head with his own plate.)

...

Later, the group was preparing to leave, and they heard the roar of a hollow – normally loud enough to be heard at great distances (provided you have enough reiryoku, or Spiritual Energy, to hear it), this one was just outside the restaurant, announcing its presence by destroying the wall. Ichigo and Rukia reacted quickly, the former using his badge to forcibly eject his soul from his body while the latter swallowed a Gikongan, or artificial soul, to do the same with her gigai without it looking as if she had a sudden heart attack. Chad brought up his arm, preparing his armored right arm; Uryu summoned his bow; Orihime called out her fairies from her hairpins, ready to attack, shield, or heal as necessary.

Before any could actually attack, however, the hollow that was somehow capable of masking its presence despite not being a high enough level hollow to speak, had already made its move and grabbed the black-haired young man from earlier. As it attempted to eat him, it suddenly roared in pain and dropped the man before lashing out and striking him hard across the head. The group began to despair as they heard the crack of bone upon the man being hit, and witnessing his soul get ejected from his body, Chain of Fate already broken. As they began attacking the hollow, trying to destroy its mask prior to any other possible destruction or deaths, they were quite shocked to see a chain wrap itself around the hollow's head and mask before the locations it was touching began to smoke. Roaring in pain, the hollow went into convulsions and tremors before finally disintegrating.

Ichigo looked around for the source of the hollow's demise, but the only person who could have even seen it who wasn't of the five was the young man, who had begun to pull his Chain of Fate back from the area the hollow had been. None of the five had any clue what was going on, but the same question was running throughout each of their minds. Ichigo was the first to be able to voice this question. "Did that plus just- WHAT THE HELL?!"

Of course, having never experienced any part of the afterlife and what happens after death, the young man's question was reasonable, perhaps even predictable: "Excuse me, but what's a 'plus'?"


	3. Chapter 2

**A/N: Here is the true second chapter, as opposed to an short extension of the first containing mostly already stated information and simply being a different viewpoint only added as its own chapter so people can compare the two if they wish to. If you have any questions or concerns about the story, feel free to either mention it in a review or PM me – if I can tell you without major spoilers I will, and if I cannot I will let you know the question will be answered eventually.**

Disclaimer: Neither Bleach nor Darker than Black belong to me; this story does not produce any form of money or profit for me.

_**CHAPTER 2**_

…...

As Hei watched the group of teenagers, he waited for an answer to his question. However it seemed he would not be getting one right now as each thing they said only added to his questions.

"Right, you're coming with us to speak to Urahara." _Why would I need to speak to some guy who runs a candy shop...?_

"Kurosaki why do you think he would know anything about this?"_ So wait, does this guy know about those plus things too?_

"He ALWAYS knows more than he tells anybody." _Sounds like a Contractor..._

"That is true... but then what makes you think he'd tell us anything?" _Yes, it is SO VERY ANNOYING when people do NOT tell you the answer to a question you have when they know it, isn't it?_

"If he doesn't tell us anything we just konso him and hope it works – he might just be tapping into his reiatsu to do that stuff, Ishida." _Two more terms they probably won't explain the meaning of._

"Which means we should try to figure out why and how he COULD do that as a human with no apparent knowledge of the afterlife." _So these people know about the afterlife but never heard of a Contractor?_

"It's possible that-"

"Will you two just shut up if you aren't going to answer my question? I would appreciate the extra information from your conversation if it wasn't for the fact you are just raising more questions and not really explaining anything." Hei was beginning to get very frustrated with the whole situation, and was seriously considering just leaving.

"...You know, I almost forgot he was there..."

…...

Quite some time later, Hei decided to follow them to Urahara's shop. He had seen it (and the shopkeeper) earlier, and remembered its name for the sole purpose of avoiding the insane place if at all possible. The only reason he was not doing so now was because the only people who seemed capable of seeing him insisted on bringing him there before actually telling him anything. He was a little apprehensive about what that information may cost, as this Urahara seemed to enjoy hoarding knowledge, and such people never shared that knowledge freely or cheaply.

Once they reached the shop, the owner opened the door as if he was expecting them. "Ah, what brings all of you here?"

The teenager so far known only as Kurosaki pointed his thumb back towards him. "This guy was killed by a hollow, but before we could kill it he somehow managed to destroy it with his Chain of Fate."

"How... _interesting_." The shopkeeper's tone seemed to become quite menacingly dark with that statement... _Why do I get the feeling I'm about to be dissected...?_

…...

Fortunately for Hei, no dissections were imminent. The shopkeeper asked him a few questions before disappearing into the back to do some research. Apparently he was quite the scientist, and knew quite a bit more about the afterlife in general than most others here – of course he still didn't tell Hei anything, under the cover of 'You'll find out soon enough.' While they waited, he decided to see if he could actually get some sort of explanation from the kids who brought him here. After a lengthy discussion about pluses, Shinigami (more commonly known as Soul Reapers, where, upon hearing that, Hei began to chuckle at the irony, utterly confusing those around him), and Hollows – the name for the type of creature who killed him.

"Strange, I thought death would be a little different from just seeing your own body with people you couldn't see before wandering around."

Kurosaki (whose given name appeared to be Ichigo) laughed. "Yeah most people aren't quite expecting this sort of thing; they tend to think they will immediately wake up in a separate place entirely."

After several hours passed during which Hei met the other inhabitants of the shop – a large man with glasses and a handlebar mustache who quite honestly frightened him a little bit, a red-haired demon of a kid named Jinta, and a black-haired quiet little girl named Ururu – the shopkeeper reentered the room. "It appears that there is another type of human with powers, similar to and yet very different from Fullbringers and Quincy. This man is most likely one of them – something called a Contractor."

"You mean there are MORE people with spiritual powers? Wait, if this guy's one of them how come he knew nothing about the spiritual realm?" _Hmm, maybe this Ichigo Kurosaki isn't quite as stupid as he acts..._

"That's just the thing; these abilities don't seem to be spiritual in nature, and in fact while he does have some sort of ability it isn't even tied to his reiatsu; did he appear to do anything odd shortly after he destroyed the hollow?"

"Not that I recall... but before the hollow attacked he did eat a LOT of food – more than any of us thought possible for him."

"Well then Mr...?"

Hei decided since he was technically dead and thus had no real reason to hide his identity, he would give his actual name. "Just call me Hei."

"Well then, Hei, would you mind explaining why your price seemed to be paid before you used your abilities instead of afterwards?"

"...That wasn't my price; I actually don't have one."

Ichigo cut off the shopkeeper's next question with one of his own. "What do you mean, his price?"

Hei decided to answer this one. "A Contractor typically has to pay a price for their abilities, generally after using them. This price can be just about anything, ranging from singing to breaking their own fingers to their physical age changing."

"And what happens if this price is not paid?"

"Nobody really knows for sure; Contractors, in exchange for their ability, lose all emotional or irrational thought, becoming entirely rational people focused solely on self-preservation above all else. Due to the rumors floating around about what happens if a Contractor doesn't or can't pay their price, the survival instinct means nobody is really willing to go against the compulsive need to pay whatever their price may be in an attempt to find out – and it is very difficult to actually capture a Contractor without loss of life on either side in order to test what would happen, so people generally don't bother."

"So you're saying people would rather _break their own bones_ than try ignoring it to see what would happen?"

"Yes. If you had a choice between breaking one of your fingers or not doing so, when not doing so may potentially lead to a very painful death, what would you choose?"

"...Point taken. So what does it mean that you don't have a price?"

Urahara, who appeared to be disappointed that he was not the person explaining this, jumped in before Hei could respond. "It means that this young man would probably be the infamous 'Black Reaper' most Contractors are terrified of. A Contractor who acts unpredictably, has power over electricity, regularly kills other Contractors and has no known price... isn't that right Hei?" At this, the scientist's eyes narrowed in Hei's direction.

_Oh, shit._


	4. Chapter 3 Reaper Unmasked

**A/N: I know I said I would be updating weekly... So you can blame/praise SomebodyLost for asking several questions and giving several ideas to me that just wouldn't leave me alone long enough for a week to pass. Keep that in mind – questions that actually make me think are likely to force me to update faster when I find an answer to them.**

Disclaimer: Neither Bleach nor Darker than Black belong to me; this story does not produce any form of money or profit for me.

_**CHAPTER 3**_

…...

_"...Isn't that right, Hei?"_

_Oh, shit._

…...

Up until that moment, the only people in the room who took Contractors seriously enough to truly believe they existed were the newly-revealed Black Reaper and Kisuke Urahara. Seeing the sudden void of emotion in Hei's face and stature proved to all those present that people incapable of emotional or irrational thought could actually exist, as both human and spirit.

"So, you figured it out. I must say that I hadn't quite expected anybody to piece it together quite that quickly, if at all. Now I ask of you, what will your elected course of action be? Were you Contractors, rationality would dictate you not reveal that information or at the very least to have incapacitated me first." All traces of any tone or inflection to his words had vanished from Hei's voice, and his reiatsu simply felt calm and quiet; for all intents and purposes, he seemed to be discussing the weather. His dark blue eyes were deadened, and beneath his gaze the group felt as if killing all of them would not be unlike stepping upon an insect, let alone possibly be a challenge or risk. This was when they decided he had earned his name, that here before them stood a true Reaper, despite the status of three members of the group as Shinigami.

"You seem to forget, Reaper, that there are quite a few more of us than you and each of us has our own array of abilities. Not the best circumstances for you, are they?" _Don't make threats you cannot back up._

"I have no rational reason to lie, so the truth of the matter is that I have faced worse circumstances before and survived. Your abilities are not entirely unknown to me either – however, these are close quarters so the archer is quite limited in effectiveness, and all the others require several seconds of preparation to use their abilities effectively. In my experience, the best way to deal with unknown abilities is to kill the target before they get a chance to use them. Knowing my ability is manipulation of electricity, and the fact that I have been a lone assassin with a higher Contractor body count than any others, it should not be difficult for you to figure out that several seconds could easily be several too many."

As he spoke, some of the others grew tense and prepared to fight. Kisuke could see the slight shift in stance from the Reaper as Ichigo and Uryu moved from their places behind him into a flanking position. If this situation wasn't defused soon, they would certainly defeat the Contractor, but he would rather not see how many would fall first.

"Now now, Hei, I don't think this is necessary. I was simply asking you if I was correct in my assumptions, then following it up with a hypothetical response to what you were implying. If we all just settle down I'm sure we can find a peaceful solution; wouldn't that be the rational choice instead of a fight you may or may not win?"

"Urahara, you can't possibly be suggesting we allow this murderer to go free!"

"That is exactly what I am suggesting, Kurosaki. Unless you would prefer yourself or one of your friends being killed before we could stop him?"

"...Fine, we won't fight him right now. No promises if we see him attacking somebody else though."

"Much as I would like to point out the discrepancy in threatening attacking an assassin if you _see_ them attack somebody, it would be for the best if we returned to the topic of discu-_nrgh_-" Hei's Chain of Fate had begun the corrosion process, with the third link from the bottom devouring the two below it. _How interesting, normally the corrosion process would both have not started the first link by now but it only generally removes one link at a time. Could this be related to the mysterious fact that Soul Society has no record of Contractors or any talk of Contractors who had been found and sent either to Soul Society or Hell?_

"...Urahara I remember the pain that process involves when it was removing a single link. How is he still standing with two links being removed at once, particularly since he was never warned about it, and why is it starting so early?"

"I assume he has a much higher pain tolerance than usual, most likely a remnant of some of his fights with other Contractors. As to the reasons why the corrosion has started early or is progressing with two links instead of one? I have no clue. The Shattered Shaft test sped up the process so it would take course over three days in your case due to the length your Chain was cut at; according to the time since his death and the original length of the Chain, I would estimate he has roughly 50 hours after death, or just under two days remaining until he would naturally Hollowfy."

"...What exactly was that, and what are you talking about? Corrosion, a shattered shaft, hollowfy? How exactly would those terms apply to whatever just happened?"

"You see, Hei, the 'monster' that killed you was a Hollow, or a 'bad' spirit. They are what people turn into if a Shinigami does not reach them and they do not pass on in time after their death. That chain on your chest, the Chain of Fate, represents the length of time remaining until you Hollowfy, or become a hollow. The process by which links on the Chain are removed is called corrosion, and that is what just happened to you. The Shattered Shaft is of no import to you as it was simply one of my experiments. Now, I have a question for you – do Contractors, despite their general lack of emotion, still have regrets?"

"That depends on the Contractor as much as it would between any other people. We still remember our lives before becoming Contractors, and we are still capable of feeling emotion, we are just incapable of acting on it if it goes against our own self interests or logic."

"Perhaps I should be more clear. Do you personally have any regrets right now about your life?"

"...No." _Odd – he almost seemed to hesitate for a split second there..._

"If that's true, the potential implications could be quite dire. Instead of sending you on immediately, I believe you should remain here for a short time so I could obtain some samples – mostly small scrapings of the metal from your chain's bottom three links, along with a reiryoku (or Spiritual Energy) sample – to study while they go through the corrosion process again and see if I can figure out why yours seems to be accelerated so much."

It was quite the shock to everybody to see Hei didn't really even seem bothered by the fact that he would have to go through that process again at least one more time before being allowed to be sent on. _I used to think Ichigo was a monster due to his spiritual pressure being so high, since a spiritual being's life force is directly represented by their reiatsu, but this guy's something else,_ Ishida quietly reflected to himself. _Maybe reiatsu isn't quite as important as sheer discipline..._


End file.
